Chevy Nova Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
63 Posts
Discussion Starter #1
So I wanted to replace my 8.2 10 bolt 4.11 with 3.08 and bought a ring and pinion and a master bearing replacement set. The new bearings fit perfectly on the carrier and the large bearing for the pinion fit well but I came to realize that the small bearing for the pinion is way too small and the spline on the 3.08 pinion is huge. I didn't notice that at first cause I was too concerned with the height matching and totally overlooked the thickness of the shaft and spline. I'll admit i'm a novice when it comes to rebuilding rear diffs but I thought since I went down in ratio that there wouldn't be no change for the pinion size except for the amount of teeth on the pinion gear and that was it. Boy was I wrong. This really threw me for a loop and made me realize I really don't have things figured out like I thought. Base on the pics can anyone tell me if the pinion on the right is even the correct one for my application? I know I have an 8.2 10 bolt set up and when I bought the 3.08 set up the description on the listing was for a 8.2 10 bolt. So why is the pinion so different? If I go this route I will need to replace the yoke and if I replace the yoke will I need to replace the driveshaft?
20200824_230456[1].jpg
20200824_230504[1].jpg
20200813_113827[1].jpg
 

·
Registered
Joined
·
1,057 Posts
I’m by no means a rear end expert but I’ve never seen a pinion with that spline on it. Your pinion yoke won’t fit either on that gear. Every rear I’ve done and that’s late 68 and up is the fine spline set up.
 

·
Registered
Joined
·
361 Posts
Could that be a truck differential and be a Richmond gear or some other manufacturer
other than stock Chevrolet gears?

 

·
Registered
Joined
·
536 Posts
You've got the wrong ring & pinion set. The course 17 spline pinion identifies it as being for the 1955-1964 8.2" gear "drop-out" style rear axle, the one that looks like a 8" or 9" Ford, where the whole pumpkin comes out of the front of a welded steel housing and the gear set can be installed sitting right there on a benchtop. It has similar dimension in several areas, and the same bolt count, but does not interchange.

You need a ring & pinion for the 1965-1972 8.2" gear Chevrolet 10-bolt C-clip axle....and make sure you don't make a second mistake of getting a set for the 8.2" BOP(Buick/Olds/Pontiac) 10-bolt, they won't cross fit either.

There is no way to make the '55-64 set fit the '65-72 Housing....you've got to return them and get the correct set.

must be someone swapped out the original 1963 housing for the later '65-67 Housing...probably either for strength, or to get 5 bolt wheel pattern, or maybe they got a deal on the later rear already set up with a 4.11 gear and that was what they were looking for.
The early 8.2 was not known for strength, a lot of guys blew them up with hot 283 and 327 engines.
 

·
Registered
Joined
·
63 Posts
Discussion Starter #5
You've got the wrong ring & pinion set. The course 17 spline pinion identifies it as being for the 1955-1964 8.2" gear "drop-out" style rear axle, the one that looks like a 8" or 9" Ford, where the whole pumpkin comes out of the front of a welded steel housing and the gear set can be installed sitting right there on a benchtop. It has similar dimension in several areas, and the same bolt count, but does not interchange.

You need a ring & pinion for the 1965-1972 8.2" gear Chevrolet 10-bolt C-clip axle....and make sure you don't make a second mistake of getting a set for the 8.2" BOP(Buick/Olds/Pontiac) 10-bolt, they won't cross fit either.

There is no way to make the '55-64 set fit the '65-72 Housing....you've got to return them and get the correct set.

must be someone swapped out the original 1963 housing for the later '65-67 Housing...probably either for strength, or to get 5 bolt wheel pattern, or maybe they got a deal on the later rear already set up with a 4.11 gear and that was what they were looking for.
The early 8.2 was not known for strength, a lot of guys blew them up with hot 283 and 327 engines.
You are spot on. The description did say it was for a 55-64 drop out. I'll return this one and look for the 65-72. Thanks
 

·
Registered
Joined
·
63 Posts
Discussion Starter #7
So I returned the 55-64 drop out and bought a 65-72 3.36. Got the pinion depth set to spec and now it's time to press the new inner pinion bearing and start assembly.
 
1 - 7 of 7 Posts
Top